Spiral runway



F. F'ARDEE SPIRAL RUNWAY May 14, 1929.

' 2 Sheets-Sheet 1 Filed Aug. 31, 1927 I lm /vnlayfiozsc'. W A TTORNEY May 14, 1929.

F. PARDEE sPIRAfi uNwAY Filed Aug. 31, 1927 2 Sheets-Sheet 12v VENTOR' B Y fl? A/Y/IPA/POEZT M TTORNE Y Patented May 14, 1929..

UNITED STATES PATENT OFFICE.

FRANK PARDEE, OF HAZLETON, PENNSYLVANIA, ASSIGNOR T0 ANTHRACI'IE SEPA- RATOR COMPANY, OF HAZLETON, PENNSYLVANIA, A CORPORATION OF PENNSYL- YANIA.

SPIRAL RUNWAY.

Application filed August 31, 1927. Serial No. 216,525.

This invention relates to improvements in spiral runways and to the method of manufacturing the same such as described in my co-pending application Serial No. 203,764.- filed July 6, 1927. In one embodiment of the invention illustrated, the spiral runway is sell-supporting. That is to say, it is strengthened vertically so that it does not require any supporting uprights. The usual form of runwaysuch as heretofore used'ior conveying materials from a higher to a lower level or runways'used in the separation of diilerent materials have been made in separate segments joined to one another in various ways. Where it has been desiri ble to pro vide an upright wall along the outer edge of such a runway, the same has usually been formed of a separate piece, bolted, bracketed or otherwise secured to the floor or bottom wall of the runway. Built-up runways are costly to fabricate and assemble.

My improved runway avoids the above objections and provides an improved runway which is light in weight yet amply strong to withstand the severe service to which this class of apparatus is subjected. I The em bodiment of the runway illustrated is formed 01 sheet metal having integral side and bot tom walls, the blank from which the runway is formed being obliquely slit or cut at spaced intervals and the portions or segments thus formed being inwardly bent and overlapped in the manner more fully described hereina'lter.

Embodiments of the invention are illustrated in the accompanying drawings in which- Fig. 1 is a front view of a self-supporting spiral runway embodying my invention;

Fig. 2 is a plan View of a runway built inaccordance with the invention;

Fig. 3 is a sectional view on line 33 0' Fig. 2;

4 is a view of a blank from which sections oi: the runway are constructed;

Figs. 5, 6 and 7 show successive steps in bending the blank of Fig. 4 to form the runscribe two lines hand 2' parallel with the way shown in Figs. 1 and '2; I 1

Figs. 8, 9. 10 and 11 are diagrammatic illustrations illustrating steps in the method of formin my improved runway; Fig. 12 1s a detail View of a modified embodiment of the invention, the view being a horizontal section;

Fig. 1.3 is a vertical section on line 13-13 of Fig. 12; i

Figs. 14: and 15 are horizontal sections of further modifications;

Fig. 16 is a horizontal section of a modification in which the runway is formed of bent plates secured by clips to upright mem bers;

Fig. 17 is a detail view of a blank from which the sections shown in Fig; 16 are formed;

Fig. 18 is a view similar to Fig. 16 but showing a self-s1upporting runway.

Referring in detail to the drawings, the runway illustrated is formed of a plurality of substantially spiral sections 1 1, each section constituting approximately a one-quarter turn of the spiral. It is to be understood, however, that if desired,-the sections may be as illustrated in Fig. 3, the sections being con-1 nected with one another by suitable splice plates 15. Or, the sections may be made each in one full turn as shown in Fig. 1. Each section of the runway comprises a side wall 20 and an integral floor or bottom wall 22 which l is inclined inwardly and downwardly toward the central axis of the spiral runway.

are secured to one another bysuitable fasten-.

ing means such as the bolts 28. Itis understood that these overlapping parts may be otherwise secured, for example, by welding, riveting, etc.

In manufacturing my improved runway, I employ a novel method which includes providing a blank B of sheet metal of suitable thickness, the sides I) and b of which are sub stantially parallel. In its initial state the blank is of approximately rectangular form and; the triangular pieces indicated by the broken lines o and (Z are out off each end. This leaves the ends 0 and f oblique. I next edges u and f. 7-1 next double over the The. floor or bottomwvall is joined to the side I blank along the dotted line indicated at Z) so that the blank has. a double thickness along one 'marginal edge. This completes the flat blank. The next step is to roll the Hat blank B into substantialliy spiral form. This is accomplished by fee ing the blank B in the direction of the arrows a in Fig. 8 toward the rolls Z. These rolls curl the blank B into substantially spiral form.

In plan, the blank is thiis curved on an arc of a. circle and in the case illustrated, the

' length of blank issuflicient to make a quarter section as illustrated in Figs. and 9. V The curled blank of Fig.- 5 is then subjected to the action of suitable bending rolls m and n so as to transversely bend portion'of the blank along the line it. This step will produce a predetermined degree of inclination which degree of inclination can. of course, be varied to sult the partlcular requirement for which the runway is to be used.

Fig. 7 illustrates the final bending effected by therolls 0, p. This provides a substantial overlapalorig the contiguous portions of the adjacent segments 26. These segments are then suitably secured to one another, for.

example, by means of bolts 28 or they may be spot Welded or various forms of interlocking joints may be securedby depressing part of one segment into a depression in the underlying-segment.

While I have illustrated the runway as built-up of quarter sections, it is understood that'this is merely illustrative and I contemplate rolling the blanks also in half turns or full turns 01', if desired, in multiple turns and'fractions' of turns.

By bending over the outer upper marginal port on, the runway 1S materially strengthened against flexure 1113, longit-udlnal or axial direction, it being apparent that this provides an outer spiral reinforcement 18 which so rigidities the runway structure that it becomes self-supporting.

However. it is understood, of course, that if desired, for certain classes of work, I may provide outer uprights such as angle ironsor the like located at spaced points around the periphery or I may utilize a central axial post having rigidly extending arms on which the runway rests and to which it may be secured. f

While I have referred to the use of bending rolls for the purpose of forming up the blank to the required shape of runway, 'it is also within my invention to cut the blank in one operation of the press and to form it to the desired shape in another operation by the use of a suitable press and dies.

In the embodiment of the invention shown in Figs. 12 and 13, the runway is composed of cast iron sections 30 of substantiall the shape shown in Fig. 13, each section being thickened at the point 32 which is located in the zone where the greatest wear occurs. Each section 30 is formed with an outwardly extending hook-like portion 3-1 which is adapted to engage the flanges 36 of an upright T-bar 38. Certain of the sect-ions 30 will be provided with integral doweldike extensions 4-0 which will engage recesses formed in the section next adjacent it so as to secure the parts in proper alignment. The sections will be bolted to one another and also to the upright by means of a suitable bolt such as indicated at 42. It is apparent that when'the bolt 42 is drawn up tight, that it will clamp the hook-like extensions 34 against the flanges of the upright 38 and will also draw the adjacent sections toward one another. Fig. 14 shows a similar arrangement in which the extensions 34 are formed with curved seats so as to fit snugly against the pipe-like or tubular upright member 44. Fig. 15 shows a slight modification of the preceding figures, the extensions 34 being shaped to interfit with an upright 46 formed of an ordinary angle bar. In the arrangement'of Fig.16, the runway is built of sheet metal plates similar in many respects to that illustrated in Figs. 1 to 10 inclusive. Each section, however, is formed with outwardly extending flanges 48 for eoaction with. clips 50 which are shaped for engagement with suitable upright as indicated at 52. The clips 50 and also the flanges 48 are provided with a suitable perforation through which the securing bolt 54 passes. Fig. 17 shows the blank from which the sections of Fig. 16 are made. The flanges 4.8 are formed by bending the blank on the dotted line 56. Otherwise, this blank is formed in substantially the same manner as the blanks illustrated in Fig. 4.

In Fig. 18 I have illustrated in plan a portion of the runway, the sections of which are provided with flanges 48 which are holtcd directly to one another by means of bolls 58. Each section of this constrlmtion will preferably, though not necessarily, be made in segments of one-eighth of a. turn. Such a runway will have suflieient stiffness to stand up itself without the use of. uprights such as angle bars or tubing.

The flanges shown need not be exactly vertical, the term upright being used herein to refer to flanges occupying a suflicient component vertically to secure the desire results. The important thing is that the depth of the runway in cross-section, that is, the vertical distance from the lowest to the highest point of it, be sui'licient to secure the desired stillness against vertical strains; to make the structure entirely self-supporting in the style shown in Fig. 1 or stifli' enough to carry the weight of the runway and its load between uprights in designs such as that of Fig. 12.

The cross-section indicated at the right and left of Fig. 3 shows that the floor is inclined downward toward the center. This, combined with the downward spiral pitch, makes the coal or other material flow at the points of discharge toward the. center and at an angle of least impact against the material ahead of it. Thus, breakage of the ma terial is kept down to a minimum. The dcsign shown permits the free discharge of materials on the inside edge of the runway and causes them to pile up around the spiral gradually from the central bottom point upward.

Various modifications may be made by those skilled in the art without departing from the invention as defined in the appended claims.

What I claim is l. A spiral runway having a floor and an outer integral upright flange having a portion overlapped to strengthen the structure.

2. A spiral runway having a floor and an outer integral upright overlapped flange of greater thickness than the floor.

3. A spiral runway having a floor and an upright flange integral therewith, said floor comprising a plurality of inwardly bent segments integral with said flange.

l. A spiral runway having a side and a bottom wall formed of a single integral sheet, said bottom wall comprising a plurality of inwardly bent overlapping segments and said side wall having an overlapped portion adapted to strengthen the structure against vertical deflection.

5. A spiral runway having a plurality of overlapping bottom segments which are integral parts of a single member.

6. A spiral runway having a side and a bottom y all formed of an integral sheet, said bottom wall having a plurality of overlapping bottom segments.

7. A spiral runway having a side and a bottom wall formed of an integral sheet, said bottom wall having a plurality of obliquely out portions bent into overlapping relationship.

8. A spiral runway having a side and a bottom wall formed of an integral sheet, said bottom wall having a plurality of overlapping bottom segments, and means for securing them in such relationship.

9. A spiral runway comprising a series of sections arranged end toend, each section comprising an integral sheet metal side and a bottom wall and each bottom wall having a plurality of cut portions bent inward from said side wall to form a series of flat inclined segments which approximately conform to a spiral.

10. A spiral runway section adapted to be combined with other similar sections to form a continuous spiral structure comprising a substantially vertical side wall and a bottom wall integral with the side wall composed of a series of inwardly bentfiat segments.

11. A spiral runway section adapted to be combined with other similar sections to form a continuous spiral structure comprising a substantially vertical side wall and a bottom wall composed of a series of inwardly bent flat segments having portions which overlap said segments being integral with said side wall and means securing the overlapped portions to one another.

12. In the manufacture of spiral runways, the method which consists in providing a flat sheet metal blank having substantially or approximately parallel sides, making a series of oblique slots which extend from one side of said blank toward the other, curling the sheet to substantially spiral form, then bending the cut portion of the curled sheet transversely inward to cause an overlapping ofthe segments between the out portions.

18. In the manufacture of spiral runways, the method which consists in providing a flat sheet metal blank having substantially or approximately parallel sides, making a series of oblique slots which extend from one side of said blank toward the other, curling the sheet to substantially spiral form, then bending the out portion of the curled. sheet transversely inward to cause an overlapping of the segments between the cut portions, then bending the out portion again to in-- crease the amount of overlap.

ll. In the manufacture of spiral runways, the method which consists in providing a flat sheet metal blank having substantially or approximately parallel sides, making a series of oblique acute angular slots which ontend from one side of said blank toward the other, curling the sheet, then bending the cut portion throughout its length substantially on the line at which the cuts terminate and then again bending the out portion along a line substantially parallel with the first line so as to decrease the included angle be tween the cut and uncut portions and thus produce a predetermined downward and inward inclination of the bottom wall of the runway.

In witness whereof, I have hereunto signed my name.

FRANK PARDEE. 

